Drawing instrument



Dec. 23, 1947, G. A. wEssN 3 3 DRAWING INSTRUMENT Original Filed Aug. 16, 1945' 2 Sheets-Sheet 1 650m; Assam WESSEN INVENTOE,

Dec. 23, 1947. e. A. wEssN 2,433,313

I DRAWING INSTRUMENT Original Filed Aug. 16, 1945 2 Sheets-Shet 2 W BWA Y.

Gzom

Patented Dec. 23, 1947 DRAWING INSTRUMENT Georg Anselm Wessn, Stockholm, Sweden Original application August 16, 1943, Serial No. 498,750. Divided and this application August 30, 1945, Serial No. 613,555. In Sweden December 3, 1942 3 Claims. (Cl. 33-103) This is a division of my application, Serial Number 498,750, filed August 16, 1943, and now abandoned.

The present invention relates to a drawing instrument which is substantially characterized by the fact that it comprises the combination with a set-off square in the form of a plate, of a support for sheets of paper, and a guide rail for the plate, said plate resting on the support and being mounted and retained by catch locks on pins provided on the support and preferably projecting through holes in sheets of paper located on the support, e. g., the holes usually punched in sheets of paper for fixing them in letter files, the said catch locks being arranged in such a way that the rail can be turned alternately, around one or the other of said pins, the plate being removably disposed on the guide rail so that it can be slid along the rail and, together with the same, be set in different angles on the underlying surface.

The object of my invention is to provide a simple and practical drawing instrument which in the first form is to be used instead of the common drawing board with set-off square and rule and which particularly insures supporting of the members of the instrument. According to a further embodiment of the invention the plate including the set-off square is provided with a number of graduated points, said points being located in such a way that th plate, when the guide rail together with the plate is. turned in such a way that one of the said points with the plate in a fixed initial position on the guide rail will lie above any given transversal line on the underlying paper, forms that angle with the line which is indicated by the number of degrees at the point in question.

By means of this device it is possible to directly draw lines forming a given angle with other lines on the drawing without using separate angle measuring instruments.

The invention i described more particularly below, reference being had to the accompanying drawing, in which Fig. 1 is a top view of the plate including a setoff square with guide rail and support.

Fig. 2 is a section on line IX- -IX, Figure 1.

Fig. 3 shows the drawing instrument with a changed embodiment of the plate.

Figs. 4 and 5 are details of the embodiment shown in Fig. 3.

In the embodiment according to Figs. 1 and 2 a set-off square 20 is shown without graduation. The set-off square in the form of a plate is located on a support 2! for a number of sheets of paper 22'. Said support is provided with two pins 23 and 24 for a rail 25 serving to guide the set-off square, said rail being provided with holes 26 for said pins. The pins are threaded at their upper ends and are provided with nuts 21 and 28 by means of which the rail 25 can be clamped against the sheets of paper and the support. Along one edge the rail is provided with a guide 29, and the setofi square '20 is provided with a U-shaped guide member 3| which can engage the guide 29 so that the set-off square can be moved along the guide, thus enabling the drawing of a number of parallel lines on the paper. By loosening the nuts 21, 28 and turning the guide rail 25 in the way shown in dot and dash lines in Fig. 1 and then tightening one nut 28 again lines can be drawn in other directions than before, and thus it is possible to draw parallel lines on the paper in any direction using one and the same set-off square.

The device according to Figs. 3 and 4 differs from the one shown in Figs. 1 and 2 therein that lines can also be drawn at a certain determined angle to lines drawn across the paper along the set-square 20. This is made possible thereby that on a line drawn midway between the points 4| and 42 the set-ofi square is provided with a number of points marked with 10, 15, 20, 30 and so on. These points are located in such a way that the uppermost edge of the plate forms that angle with the transversal line which is indicated by the number of degrees at the point in question if the plate is moved to its lowermost (or uppermost) position on the guide 29 and if the guide rail 25 is turned so much that the point in question which is provided with angle indication, is situated right above a line 44 drawn at the edge of the support. The line 44 is preferably white on black bottom so that it is clearly visible through the set-off square or through apertures in the setoff square. Thus, if the guide rail 25 is turned together with the set-oil square 20 so that the point marked with 15 comes right above the line 44, after the latter has been moved to the shown end position, and if then the set-ofi square is moved upwards along the guide rail, a number of lines parallel to one another can be drawn, all of said lines forming an angle of 15 to any line running transversally to the paper. In the same way other angles can be obtained by causing the point corresponding to the desired angle indication to come right above the line 44. If the guide rail has been swung out from the pin 23, the set-off square is set on the guide rail in the uppermost end position of the guide rail for the determination of the angle. The device shown in Figs. 4, 5 also differs in another way from the one shown in Figs. 1 and 2 in that the pins 23 and 24 are not threaded and the nuts 21 are omitted. Instead thereof the pins 23 and 24 are completely smooth, and the guide rail 25 is preferably on the underside around the holes 26 provided with an elastic jam element 45 made of steel thread which will catch the pins 23 and 24 when the guide rail 25 is brought back to the said pins. Consequently, the guide rail is retained in its place.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A drawing instrument, comprising a set-offsquare in the form of a plate, a support for sheets of paper, and a guide rail for the plate, said rail resting on the support and being mounted. and

retained by catch locks on pins provided on the supportand preferably projecting through holes in sheets of paper located on the support, e. g. the holes usually punched in sheets of paper for fixing them in letter files, the said catch locks being arranged in such a way that the rail can be turned alternately, around one or the other of said pins, the plate being removably disposed on the guide rail so that it can be'slid along the rail and, together with the same, be set in different angles on the underlying surface.

2. A drawing instrument according to claim 1, in which the plate is provided with a number of graduated points, said points being located in such a way that the plate, when the guide rail together with the plate is turned in such a way that one of the said points, with the plate in a fixed initial position on the guide rail, will lie above any given transversal line on the underlying paper, forms that angle with the line which is indicated by the number of degrees at the point in question.

3. A drawing instrument according to claim 1, in which the catch locks of the guide rail consist of elastic jam elements which are located around the holes in the guide rail and arranged in such a way that they engage the pins in questionso thattheguide rail is held in position on one or the other :of the said pins and sometimes on both pins.

GEORG AN SELM WESSEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 930,340- Roch et a1. Jan. 3, 1911 521,597 Alt'peter June 19, 1894 

